Do you have nav? If yes then check what version of the SD card you have. the original 2.11 had the A2 card, when 3.02 came along it required the new A3 card, 3.22 still used the A3 card but when 3.51 came out a new A4 card was needed.

If you do not have nav then log onto syncmyride.com and download the free version checker tool and follow the instructions to check what you have.